I have the Jabiru 3300 with an MGL avionics EMS.  I have not had a first start on the engine yet, but all wiring is complete.  I have removed a spark plug from each cylinder and cranked the engine to verify the instrumentation.  My RPM's indicate, but I am not seeing any oil pressure indication.  What would be normal while cranking?  Does anyone know what setting to use in the MGL EMS for the standard Jabiru Oil Pressure sensor?

All other instrumentation from the engine is working.  Once I get this worked out I will be ready for a first engine start. 


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I'm sure you checked this, but the engine does have oil in it? 

If it's a new engine, it's unlikely the sensor has failed since they are dyno'd prior to shipment, but if it's a used engine, the VDO-type mechanical oil pressure senders are notorious for failing.  I had a couple of "pattern part" senders fail (copies of the original made by others) and tried a genuine VDO sender and it did no better.  I went to a "Swift" sold-state sender as sold by Spruce - theoretically, they never wear out!  However, they require some additional wiring - a power and ground wire in addition to the signal wire, but it works great with my MGL XTreme EMS once I calibrated it.



Full of oil and even warm in my 60 degree heated shop.  Daughter and I even filled the oil cooler with oil prior to final installation.  I would also expect the VDO sensor to still be good.  I am planning to switch to the Swift sensor at some future condition inspection.  I have sensor power and ground at a terminal block on the engine side of the firewall since I needed it for the MGL amp sensor and the Proximity switch that I am using for the RPM readout.

Does your VDO sensor have two terminals, one of which is marked "G?"  Years ago when I wired my engine, I assumed the "G" was for "Ground" and grounded that terminal and also had zero pressure reading.  A quick call to Pete at Jabiru USA and he told me the "G" was for "Gauge," not ground.  So, the "G" terminal is the signal terminal and the wire from it goes to your oil pressure input terminal.


John, I just sorted all this on my 3300 with MGL. I will check the setting for Oil Px and post it later tonight. How are you getting your RPM?

I used a  Taiss 1PCS NJK-5002C NPN NO(Normally Open) 10mm Hall Effect Sensor Switch DC5-30V Inductive Proximity Sensor Switch Induction Magnetic Which was just $10 on Amazon.  Amazon Link  There are a number of similar sensors on the market.  By using a larger sensor I was able to position it much further from the target.  It picks up the screws on the magnets.  The sensor requires power and ground which I supply from a terminal block on the firewall with power coming from the avionics fuse and ground from the RDAC terminal strip.  It then outputs a pulse on the third wire.  I manufactured a custom bracket using fastened with one existing bolt and one drilled and tapped screw. 

I initially tried an Ebay cheapo Chinese Hall-Effect sensor and they would work great, but I found them to be unstable when heat-soaked.  That would result in erratic tach readings if I briefly shut down on a very hot day and then restarted to fly again.  Most of the inexpensive senders are not heat-rated.  I finally used a genuine Honeywell GT-1 gear tooth sensor that is rated for 150C and even 160C "for short periods."  I never had another tach stability problem.


Good point.  I might even try to get a Telemechanique or Turck (Allen Bradley) sensor from one of my old suppliers.  The Turck are especially rugged. 

Thanks that is my fall back, I will run a lead from my magneto through a 10K ohm resistor to rpm 1 input and see how that goes first. To get your thread back on track I will check the oil px setting for you.

John, pics below for oil temp and oil px. cheers.


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